The present application claims priority from Taiwan Application No. 089113711, entitled xe2x80x9cHeat Sink Capable of Having a Fan Mounted Aslant to the Lateral Side Thereof,xe2x80x9d filed on Jul. 6, 2000.
1. Field of the Invention
This invention relates to a heat sink for a computer chip, such as a Central Processing Unit (CPU) chip, and more particularly to a heat sink where a fan is mounted aslant to the lateral side thereof.
2. Description of the Related Art
As the function and complexity of computer chips have increased recently, the heat generated by computer chips has also increased. Additionally, the heat dissipation space of computer chips has become smaller and smaller since the information products emphasize small sizes and high clock rates. Therefore, how to effectively dissipate the heat in a limited space to maintain the performance of the computer chips becomes an important issue.
FIG. 1 is a schematic diagram of a prior art heat sink 10 mounted on a CPU chip 12. The heat sink 10 comprises a base 20, a heat dissipation unit 22 and a fan 24. The heat dissipation unit 22, having a plurality of heat dissipation fins 23, is mounted on the base 20. The fan 24 is mounted on the heat dissipation unit 22. In an exemplary computer server, the total height H of a housing 14 above a motherboard 16 is only 44.86 mm. Thus, after positioning a CPU slot 18 and the CPU chip 12 on the motherboard 16, only a height h of 27 mm is available for mounting the heat sink 10. As shown in FIG. 1, the fan 24 is so close to the upper cover of the housing 14 that the air entry area 26 is too small and the space for heat dissipation is limited. Therefore, the quantity of the air that can enter the fan 24 is quite small or close to zero. The low air flow causes the fan 24 to run idle, and no air is swept into the heat dissipation unit 22. Thus, the air from the fan 24 can not take the heat generated by the CPU 12 chip away, and the fan 24 can not effectively dissipate the heat from the CPU chip 12.
In addition, since the fan 24 is mounted on the heat dissipation unit 22, the location of the fan axis will cause the central area of the heat dissipation unit 22 to have little or no air flow or to have turbulent air flow. These phenomena cause the temperature in the central area of the heat dissipation unit 22 to be quite high. Since the CPU chip 12 is located under the heat dissipation unit 22, the effect of heat dissipation is greatly reduced.
One aspect of the present invention is to provide a heat sink where a fan is mounted aslant to the lateral side of the heat sink. The heat sink of the present invention not only enlarges the air entry area of the fan, but also can effectively sweep the air into the central area of a heat dissipation unit to achieve an improved heat dissipation effect.
The foregoing is a brief description of some deficiencies in the prior art and advantages of this invention. Other features, advantages and embodiments of the invention will be apparent to those skilled in the art from the following description, accompanying drawings and appended claims.